Fire-prevention means for internal-combustion engines.



F. A. SHAW.

FIRE PREVENTION MEANS FOR INTERNAL COMBUSTIGN ENGINES. APPLICATION man FEB. 25, I915.

1,165,,91Qn Patented Dec. 28, 1915.

FREDERICK A. S HAW. OF PROVIDENCE. RHODE ISLAND.

FIRE-PREVENTION MEANS FOR INTERNAL-COMBUSTION ENGINES.

Application filed February 25, 1915.

To all ir/mm 2'1. may concern:

Be it known that I, Flunmmcn A. Straw, a citizen of the United States. residing at Providence. in the county of Providence, State of llhode Island. have invented certain new and useful Improvements in Fire- 'lrevention Means for lnternal-Combustion Engines. of which the following is a specification.

My invention relates to fire-prevention means for gas-engines, 'iarticnlarl as applied to the fllel-supply-devices or carbureters thereof.

The object of my improvement is to provide means for automatically closing the airintake of the carbureter whenever backfiring occurs therein whereby the supply of oxygen is shut off and the fire extinguished before it can spread.

My improvement is intended for use particularly with internal-combustion engines employed in automobiles and motor-boats to prevent the ignition of the highly volatile vapors which accumulate in the inclosed spaces about the carbureter, such as under the engine hood or in the bilge of the boat.

The invention is fully described in the following specification, illustrated by the zu'companying drawings, in which like letters of reference designate like parts.

In the drawings :F igure 1 is a vertical, sectional view of a standardtype of gas-em gine carbureter showing my improvement applied thereto: Fig. 2 is an end view of the automatic valve or damper which acts in the presence of fire to close the air-intake of the carbureter: Fig. 3 is a detail View of the fusible link which normally maintains the air damper open: and Fig. 4 is a general view of another type of carbureter having two air-intake ports or openings with my improved device shown as applied to each of these.

Referring first to Fig. 1. C designates a carbnreter of well-known type comprising the main bowl portion B. for containing the fuel supply shown at g; the mixing-chamher M; and air-intake A.

K. the movable float for controlling the gasolene valve Y and N is the needle-valve for regulating the spray of vapor in the mixing-chamber M.

'l is the tln'ottlewalv'e for controlling the admi sion of gas through the pipe P which pted to be connected to the engine Specification of Letters Patent.

Patented Dec. 28, 11915.

Serial No. 10,564.

manifold. not here shown. In the type of carburetor here illustrated the air-intake A 18 formed as a pipe-bend or elbow mounted on the cover or cap E which closes the top of the bowl B. Air is admitted through the openmg a of the intake A and normally passes through a restricted passage (1. downwardly into the mixing-chamber M. as indicated by the arrow 00, Fig. 1. For increasing the amount of air admitted to the carbureteiwhen the engine is running at high speed a. spring-controlled plunger valve \V is emplovcd arranged to normally close the greater portion of the intake-pipe A. The valve 3V seats against a ring-like face (t extending part way around the interior of the pipe A and when the suction within the earbureter increases with the increase in speed of the engine the *alve \V will be drawn back against the action of its spring 20 to provide a more extended entrance space for the air.

As before indicated, my improved device is applied directly to the air-intake of the carbureter and consists essentially of an automatic damper or check-valve Dadapted to be closed through the effect of a back-fire from the engine. My improved damper may be constructed in any convenient form or with any suitable arrangement of parts as required, the present showing being merely one embodiment of the invention.

As illustrated in Fig. 1, I have preferred to show my device as a complete attachment in itself to adapt it to be applied to the carbureter by simply screwing it on over the intake opening. For this purpose the airintake-pipe A is threaded on its exterior at a and screwed onto the threads is a ring or flange R having its opening formed with abeveled seat '7.

Projecting from the top of the ring' R are two ears 0*, 1*, see Fig. 2, adapted to receive a hinge-pin or bolt 71..

Mounted to swing on the hinge-pin h is l the closure or damper D which is formed to fit the beveled seat 1 in the ring R. If re-v quired a suitable packing-ring '1" can be inserted in the opening of the ring-member R to provide for a closer fit of the damper D. The damper D is hinged on the pin it by means of two ears or lugs (Z, (Z, one of which is extended to form the rearwardly projecting arm a" through which the valve is automatically controlled. A wire spring S is coiled around the pin 71. with one of its ends .s' engaging a hole in the lug (I while its opposite extremity .v' bears on the top of the ring It. as shown in Fig. 1. The spring S is so arranged that its tendency is to close the damper l) against its seat- 1' in the ring R.

Fastened to the end of the arm (1' of the damper I) is a wire link or connection 7 extending through an opening r in the. ring It. The end oi the connection I is tormed ed to fit into and close the opening 1' in Y the top of the ring-member It when the damper I) is closed against its seat.

livoted on a screw 0 screwed in :1 lug r at the bottom of the ring-member R is a pawl or latch adapted to hold the damper I) in its closed position after it has been operated by its spring S upon the release of the fusible link F. The forward end of the latch O is formed with a detent shoulder 0' over which the edge. of a lug (F on the damper l rides as the latter closes against its seat. and a wire spring a. is arranged to hold the latch in its operative position as shown. The purpose of the latch O is to lock the damper I) in its closed position to prevent it from being forced open should an explosion occur in thecarbureter after the air intake is once sealed. In most cases the latching-means for the damper would probably not be required but I prefer to provide it as a precautionary measure.

In Fig. .i I have illustrated another type of carburetor which is provided with two air-intakes for supplying air to the mixture. At the top is the valve-controlled intake A while near its bottom, opening into the mixing-chan'iber through the bowl B, is the main intake (l. 'ith carbureters of this design my automatic or self-closing damper is applied to both intake-openings, the arrangement being the same in each instance as that illustrated in Fig. 1. l sually, with the type of carburetor illustrated in Fig. 4, the main air-intake G is connected by a flexible pipe or duct to a hot-air drum which surrounds the cxhaust-manifold of the engine. Through this means the air drawn into the carbureter is heated from its contact with the engine exhaust-pipe and in-this way the fuel-mixture is rendered more volatile so that better combustion is secured in the cylinders. \Vhere it is desired to employ the hot-air pipe as above described it can be provided with an enlarged hood to surround the intake (l and inclose the automatic danmer-mechauism without interferingwith its action. .In this case the hood or air-duct connection for the intake is either made with av door or opening to allow the manual setting of the damper when required. or else it is arranged to be easily detached from the intake A for the same purpose.

In the present embodiment of the invention I have described and illustrated my automatic damper in its simplest form. constructed as a hinged cap or cover. It is obvious. however. that the damper I) might be made in several other forms; such. for

instance, as av butterfly valve or a Closure of the sliding-shutter type. Other arrangements of the operating and releasing mechanism could also be substituted for the de vices here shown, the present arrangement being merely a convenient one to illustrate. The method of operation of my improved device is as follows: The ring-member or alve-seat R is applied to the intake-pipe ot' the ca-rbureter by screwing it over the threads previously provided on its surface. or by fitting it in place in any other suitable manner. \Vith the damper 01" valve I) raised into open position as shown in 'Fig. 1 the t'use-link F is hooked over the end of the connection Z and the hook Z to hold the valve in place so as not to obstruct the mouth or opening of the intake-pipe A. Under normal conditions, with the engine running properly, the air will have free entry through the intake A to the mixing-chamber M to provide for the functioning of the carbureter in the usual well-known manner. In some cases, where the carbureter is not properly adj usted or where other causes tend to feed a too rare mixture into the engine cylinders, back-firing will take place. A back-fire occurs when the exhaust-valve of the operative cylinder is closed and the inlet-valve opened, and consequently the explosion will seek its only outlet back through the carbureter. In some instances improper setting of the magneto, or other electrical make-andbreak apparatus. will cause faulty timing of the spark discharges in the cylinders and this will also cause back-tiring through the carbureter. The only vent for the exploding gases from the carbureter is through the air-intake thereofi.

The purpose of the present invention is to provide an automatic check-valve for closing the carburetor intake as soon as a backfire occurs so that no more air will be admitted thereto and consequently the ignited gases will be extinguished and the fire will be prevented from spreading to other parts through the intake of the carbureter the heat therefrom will fuse the link F and release the wire connection Z. lVith the'connection Z freed from its holding-means the spring S will close the valve or damper D against-its seatin the ring R and the latch 0 will then lock it in place. As the damper D closes into position the stopper 6 will be carried up against the flaring edge of the hole 1' in the ring R to close this opening and in this way the mouth of the intake is practically hermetically-sealed toprevent the ingress of air to the earbureter. In this way if the gas in the carbureter has already been ignited by the back-fire from the engine it will be extinguished for lack of oxygen. On the other hand, ifthejirst explosion has failed to ignite the mixture in the carbureter the checking of the air supply will prevent such i nition and will also prevent further back-fi iing from the cylinders. After the fire has been extinguished, to adapt the carbureter for further service it is only necessary to open the check-valve or damper D again and secure it in raised position by means of a new fuse link as first described.

I have found from experience that most fires in automobiles or motor-boats are not caused primarily from the discharge of the ignited gases from the carbureter at the first back-fire, but usually only after the fire has spread to the gases inside the carburetor itself. As will be seen from reference to Fig. 1, a considerable supply of gasolene or other fuel is maintained in the carbureter reservoir under normal conditions and when the gases in the mixing-chamber are ignited the vapor will be drawn up through the spray-nozzle to further feed the flame. Under these conditions an exceedingly hot fire is soon generated, and the flames bursting from the intake of the carbureter will,

invariably ignite the vapors which collect under the hood of the engine of the automobile, or in the bilge of the craft in which the motor is located. In this way the fire is caused to spread and consume everything inflammable with which it comes in contact. The danger from fires through such causes is particularly prevalent in motor-boats or yachts employing internal-combustion engines on account of the many inclosed places in which the gasolene vapors collect.

Arrangements have heretofore been devised for shutting off the gasolene supply for the carburetor when a fire occurs therein, but these have not been found generally efficacious for the following reasons: As before stated a considerable amount of fuel is always carried in the carbureter float-chamber, suiiicient to feed a fire for an extended period, and with the carburetor once aflame it is difficult to extinguish it by any means other than cutting off the air-supply. With my present improved apparatus the supply of oxygen necessary to combustion is shut off immediately a back-fire from the engine occurs or, in fact, if the gas in the carbureter becomes ignited from any other cause, and in this way the fire is soon extinguished and prevented from spreading. It is a well known fact that gasolene itself cannot be ignited, but only the vapors are inflammable when mixed with air. By taking this principle into consideration I have been able to devise a most effectual fire-prevention means for use with internal-combustion engines, and it is called to attention that my invention might be applied to use with other fuelsupply devices besides the generally used carburetersv such, for instance, as injectors or the like.

-As before mentioned my invention is capable of many different adaptations for use with various types of carbureters or fuelinjectors and the manner of applying it thereto can be varied as required. If desired, it can be constructed as a built-in part of the carbureter itself and arranged to be completely inclosed within the casing there of. Various other modifications might also be made in the structure and arrangement of the parts of my device without departing from the spirit or scope of the present invention; therefore, without limiting myself to the exact construction shown.

What I claim is 1. In acarbureter for internal-combustion engines, the combination with a mixingchamber for the fuel and air, of an airintake leading thereto, a damper for closing said intake, means for operating said damper, means for maintaining said damper normally open, fusible means adapted to be ruptured by heat to release the damper, and automatically-operated means for locking said damper in closed position to prevent it from being forced open by explosions within the carbureter.

2. In a safety-device for gas-engines, the

combination with a carbureter having a mixing-chamber and an air-intake leading thereto, of a damper adapted to be applied to said intake, means for operating the damper to close the intake, means for holding said damper normally open, and a fusible link forming a part of said holding-means and arranged within the intake opening to adapt it to be ruptured by the effect of heat from a back-fire to release the damper and cause it to close.

3. In a fire-prevention means for gas-engines, the combination with a carbureter having a mixing-chamber and an air-intakeleading thereto, of a damper hinged-on the intake opening, a spring for operating the damper to close the intake, means connected with said damper for normally holding it in open position, and a fusible link forming part of the holding-means for the damper and arranged across the intake opening to adapt it to be fused by the heat of a backfire in the carbureter.

-l. In a safety-device for gas-engine carbureters, the combination with the air-intake thereof, of a ring-member formed with a valve-seat and adapted to be attached to the intake, a valve hinged on the ring-member to adapt it to close against the seat therein, a spring for closing the valve, a hookedmember fastened to an arm on the valve, a second hook fixed on the interior of the ringmember, and a fusible link for connecting the hooks to hold the valve in open position.

5. In a safety-device for gas-engine carbureters, the combination with the air-intake thereof, of a ring-member attached thereto,

a valve hinged on the ring-member and adapted to seat thereagainst, a spring for operating the valve to close the intake, a hooked member connected with the valve, a second hook on the ring-member, a fusible link connecting the two hooks to hold the valve in open position, and a spring-operated latch for locking the valve against its seat after it has been closed through the release of the holding-means.

In testimony whereof I aflix my signature in presence of two Witnesses.

FREDERICK A. SHAW.

Witnesses:

HERBERT K. ALLARD. GEORGE A. WHITE, Jr.

Copiesof this patent may be obtained for five cents each, by addressing the "Commissioner of Patents,

' Washington, D. 0. 

